The long term goal of the project is to study the etiology and mechanism of gastroschisis. Gastroschisis is a congenital fissure of the abdominal wall that permits extrusion of abdominal contents. It is also noted in the offspring of young mothers who often smoke. The incidence of gastroschisis has been increasing in many countries in recent years. PI has developed a mouse model to study the etiology and mechanism of gastroschisis. The model indicates that gastroschisis is caused by the combination of carbon monoxide and protein/zinc deficiencies during gestation. PI proposes to collect more data to test the validity of the model. Specific aims of the project are (1) to determine whether gastroschisis is caused by the combination of gestational carbon monoxide and protein/zinc deficiencies in the maternal diet, (2) to investigate the mechanism that gastroschisis is caused by excessive embryonic cell death in the umblical region of the developing embryo, (3) to invetsigate that gastroschisis may be prevented by the supplementation of maternal diet with protein and zinc. A 3 way factorial experimental design will be used. Pregnant mice will be fed different combinations of protein-zinc diets during gestation, exposed to various levels of CO from gestation days 8-18, fetus will be examined for gastroschisis, 10 day embryos will examined for cell death. The embryos will sectioned and stained by TUNEL method to study cell death.